Thoughts on Passive Bi-Amp for Electromotion

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Perhaps the crossover can be split and speaker binding posts added to the bottom panel if there's enough space.

Hola, if you pinch the + and the - and pull them out, you get the banana female connectors. See the attatch 16649. These connectors are very friendly to use. You are allow to use bare wire too. Just press the + or the - and insert the bare wire, release the buttom, and there you are. Happy listening!
 
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All respect to Northy's comment, because what he says is correct, but you're not there yet. Most people are content to use one channel per speaker, especially in a Home Theatre configuration. Also, you probably already know this, but your EM'S will need at least 100 hours of break in time before you should be making any judgments about their sound. If I were you, I would use my remaining 2 channels for a second pair of peripheral surrounds (pretty sure I've just coined a new term :D)
 
Hola, if you pinch the + and the - and pull them out, you get the banana female connectors. See the attatch 16649. These connectors are very friendly to use. You are allow to use bare wire too. Just press the + or the - and insert the bare wire, release the buttom, and there you are. Happy listening!

Thanks for the Accurate information!
 
Hola. There are HT receivers, like the Onkyo TX-NR828, where you have 11 separated mono power amplifiers. You can bi-amp, the front speakers. It is a feature on this model. But, the Electromotions are not capable for this feature. The Vistas, and the Theos are. With the Ethos and up to the Summits X, con can not bi-amp. You have an internal power amplifier to drive the woofers. A reason why you have only two binding posts. On the Theos or the Vistas, you do have four binding posts. Any Martin Logan model with 4 binding posts, you can bi-amp. Happy listening!
 
Can't you just remove the rubber + and - rubber inserts to reveal the input for banana pugs on the back of the binding posts?
 
anyway to rewire the insides and add two posts? Just seems like a waste of amps to have two channels sitting there doing nothing.

Rewiring to add another set of posts is not that simple. Conceptually, it involves removing the trace (connection) between the low-pass filter and the input to the high-voltage step-up transformer. Once this is done, you can proceed to add another set of binding posts to support bi-amping. I put together a conceptual drawing to help illustrate the modification steps. It is very high-level and I'm sure there are lots of details missing. But it gives you a general idea about how involved this modification can get.
 

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I believe the em els does support banana plugs, you need to removed the plastic caps. The only thing that it won't accept are spade connectors. As for bi amp, i tried it with my old onkyo receiver and paradigm speakers and it didn't make any difference. Unless you have a very high end set up and 2 separate amps I doubt it will make a difference.
 
Thanks Spike. Not sure if I will give it a go or not. Doesn't really look that complicated. My main concern is not realizing something about how it is wired and frying the speaker and or receiver. If it is as straight forward as your diagram this is simple.
 
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I believe the em els does support banana plugs, you need to removed the plastic caps. The only thing that it won't accept are spade connectors. As for bi amp, i tried it with my old onkyo receiver and paradigm speakers and it didn't make any difference. Unless you have a very high end set up and 2 separate amps I doubt it will make a difference.
And if you don't like banana plugs because of the loose fit, here are some lockable ones, very reasonably-priced. I use them on the jumper cables of my SL3s.

http://www.amazon.com/GLS-Audio-Loc...=8-11&keywords=orange+county+speaker+banana+4
 
Thanks Spike. Not sure if I will give it a go or not. Doesn't really look that complicated. My main concern is not realizing something about how it is wired and frying the speaker and or receiver. If it is as straight forward as your diagram this is simple.

Don't waste your time, money, and energy to modify any speaker for passive bi-amping/bi-wiring. The only thing that does is make cable manufacturer's richer and you possibly screwing up your nice speakers. If you're going through the passive crossover all the benefits of a driver having it's own amp goes right out the window like having direct control of the driver and wasting amp power by amplifying the entire frequency range instead of a limited band. Active bi-amping is a different story and completely worth doing if you have the time, money, and energy to do it. You'd remove the passive crossover. Hook each driver up to the amp directly (though with the panel you'd still have the step up transformer) and having an active crossover split the signal before the amps. Personally I'd like to go active bi-amping with some ESL's at some point in the future.

Read more here:
http://www.chuckhawks.com/bi-wire_bi-amp.htm

See also:
http://www.martinloganowners.com/fo...-The-case-for-active-crossovers-and-bi-amping

JonFo on this forum has converted an ML SL3 to an active design for his HT:
http://www.martinloganowners.com/fo...-channel-speaker-%96-a-design-and-build-story
 
If you're going through the passive crossover all the benefits of a driver having it's own amp goes right out the window like having direct control of the driver and wasting amp power by amplifying the entire frequency range instead of a limited band.
I agree that active crossover done correctly is the ultimate goal, but to dismiss passive biamping is, in my opinion, short-sighted. The Summit X, for example, is an example of passive bi-amping with regards to the full-range signal from your amplifier driving the panels through the passive crossover circuitry. Furthermore, there's an extra circuitry to convert high-level signal to low-level, in order to feed into the internal amplifier driving the woofer. Beside the Summit-X, there are other speaker manufacturers with similar implementation where there's an internal amplifier driving the woofers. Are we to dismiss all of these speakers on the market as not having any sonic benefit at all?
On the subject of active bi-amping, if I don't design my crossover circuitry to match with the characteristic of the intended drivers (frequency response & crossover slopes), I will end up with worse performance than staying with the passive bi-amping route. In summary, there are pros and cons to both approaches and it's up to the owners to decide which trade-offs he's willing to live with.
 
In my opinion, modifying a speaker such as the electromotion for passive biamping is a waste of time, effort, and money. The potential downsides far outweigh the potential for sonic improvements in this scenario.
 
Very good food for thought guys. Yes, my intention was to active bi-amp them, but as I suspected it is more complex than it seems. If it was an easy fix I was definitely game to try.
 
ML also abandoned this on the Summit X.

The legacy Summit had 4 posts per speaker requiring a "jumper cable", which introduced it's own compromises.

GG
 
If you split the ESL xo from the woofer xo and passively bi-amp them, it's not a waste of time as you are removing the high-current woofer load from the top amp, and a much smaller amp will suffice to drive only the ESL portion.
 
Hola, if you pinch the + and the - and pull them out, you get the banana female connectors. See the attatch 16649. These connectors are very friendly to use. You are allow to use bare wire too. Just press the + or the - and insert the bare wire, release the buttom, and there you are. Happy listening!

I know you wrote this a long time ago Roberto, but today it was very very helpful :) I was somewhat baffled by these posts, but sure enough on here was the answer!!
 

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